Re: [ARSCLIST] Internet audio: What do you expect of it ?

[Jerry Hartke <jhartke@xxxxxxxxxxxx>]

Being rather ancient, I go back to tube amplifiers of the 1940's, and am
confused about the reference to "solid state distortion." Does this refer to
hard clipping when transistors are overdriven? Although tube amplifiers clip
more gradually, they also introduce distortion in the process. Thus neither
form of amplification should be overdriven.

Tube amplifiers are limited by their output transformer that matches the
high output impedance of the tubes to a low load impedance. This transformer
significantly degrades frequency and phase response, placing severe
constraints on the amount of negative feedback that reduces the inherent
distortion of the amplifier. I paid as much as $100 back in the '50s for a
superior output transformer, and still struggled to achieve 20-20,000 Hz
with 0.1% intermod.

Solid state amplifiers normally do not have output transformers, and thus
can use greater amounts of negative feedback. This results in much lower
distortion, better frequency (and transient) response, and superior damping
than that achieved by most tube amplifiers. It seems that solid state
amplification would be preferable provided that amplitudes stayed within
their dynamic range (always necessary for fidelity.)

I do not disagree with those, including myself, raised on tube amplifiers
and accustomed to their limited frequency response and somewhat higher
distortion. Many of us like this "sound." However, we should not confuse
this preference with faithful reproduction.

Jerry Hartke

> -----Original Message-----
> From: Association for Recorded Sound Discussion List
> [mailto:ARSCLIST@xxxxxxx] On Behalf Of Steven C. Barr(x)
> Sent: Tuesday, December 18, 2007 11:06 PM
> To: ARSCLIST@xxxxxxxxxxxxxxxx
> Subject: Re: [ARSCLIST] Internet audio: What do you expect of it ?
> 
> ----- Original Message -----
> From: "Don Cox" <doncox@xxxxxxxxxxxxxx>
> > Hello Steven
> > On 18/12/07, Steven C. Barr(x) wrote:
> > > ----- Original Message -----
> > > From: "Roger and Allison Kulp" <thorenstd124@xxxxxxxxx>
> > >> I see it as a latter day version of the all-tube FM tuner,rather than
> > >> the CD/phono amp.
> > >>
> > > Keep in mind that the appeal of vacuum-tube audio equipment is NOT its
> > > "perfect" reproduction (which probably doesn't...in fact,
> > > CAN'T...exist?!) but rather the fact that the distortion it generates
> > > is much more enjoyable for steady listening than its solid-state
> > > equivalent...?!
> >
> > Yes, but if you feed an unpleasantly distorted signal into a box with a
> > tube in it, the tube will not magically remove that unpleasantness.
> >
> > Remarkable things can be done with software to improve a nasty
> > recording, and I expect such software to improve in the future, but a
> > simple tube based amplifier stage cannot make a silk purse out of a
> > sow's ear.
> >
> That, actually, was my point...! If an audio signal has been, at any
> point in its life, been subjected to solid-state distortion...
> 
> 1) The listener has my deepest sympathy...
> 
> 2) AND...the signal will never again sound good, regardless of what
> it is played on/through...!
> 
> Steven C. Barr